/**
 * Created on May 6, 2008
 *
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License only.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA 
 */

package com.aelitis.azureus.ui.selectedcontent;

import org.gudy.azureus2.core3.download.DownloadManager;
import org.gudy.azureus2.core3.util.Debug;
import org.gudy.azureus2.plugins.download.Download;
import org.gudy.azureus2.pluginsimpl.local.PluginCoreUtils;

import com.aelitis.azureus.core.util.CopyOnWriteList;
import com.aelitis.azureus.ui.common.table.TableView;

/**
 * Manages the currently selected content in the visible display
 * 
 * @author TuxPaper
 * @created May 6, 2008
 * 
 */
public class SelectedContentManager {
    private static CopyOnWriteList<SelectedContentListener> listeners = new CopyOnWriteList<SelectedContentListener>();

    private static volatile ISelectedContent[] currentlySelectedContent = new ISelectedContent[0];

    private static volatile String viewID = null;

    private static volatile TableView tv = null;

    public static String getCurrentySelectedViewID() {
        return viewID;
    }

    public static void addCurrentlySelectedContentListener(SelectedContentListener l) {
        if (listeners.contains(l)) {
            return;
        }
        listeners.add(l);
        l.currentlySelectedContentChanged(currentlySelectedContent, viewID);
    }

    public static void removeCurrentlySelectedContentListener(SelectedContentListener l) {
        listeners.remove(l);
    }

    public static void clearCurrentlySelectedContent() {
        changeCurrentlySelectedContentNoTrigger(null, null, null);
        // Always trigger selected content listeners since toolbar relies it
        // them to reset the toolbaritems if something that didn't use
        // SelectedContentManager modified the toolbaritems states
        triggerSelectedContentListeners();
    }

    public static void changeCurrentlySelectedContent(String viewID, ISelectedContent[] currentlySelectedContent) {
        changeCurrentlySelectedContent(viewID, currentlySelectedContent, null);
    }

    public static void changeCurrentlySelectedContent(String viewID, ISelectedContent[] currentlySelectedContent, TableView tv) {
        changeCurrentlySelectedContentNoTrigger(viewID, currentlySelectedContent, tv);
        triggerSelectedContentListeners();
    }

    private static void changeCurrentlySelectedContentNoTrigger(String viewID, ISelectedContent[] currentlySelectedContent, TableView tv) {
        if (currentlySelectedContent == null) {
            currentlySelectedContent = new ISelectedContent[0];
        }
        /*
         * System.out.println("change CURSEL for '" + viewID + "' to " + currentlySelectedContent.length + ";" + (currentlySelectedContent.length > 0
         * ? currentlySelectedContent[0] : "") + Debug.getCompressedStackTrace());
         */
        if (currentlySelectedContent.length == 0 && SelectedContentManager.viewID != null && viewID != null
                && !viewID.equals(SelectedContentManager.viewID)) {
            // don't allow clearing if someone else set the currently selected
            // System.out.println("-->abort because it's not " + SelectedContentManager.viewID);
            return;
        }

        synchronized (SelectedContentManager.class) {
            boolean same = SelectedContentManager.tv == tv;

            if (same) {

                same =
                        SelectedContentManager.viewID == viewID
                                || (SelectedContentManager.viewID != null && viewID != null && SelectedContentManager.viewID.equals(viewID));

                if (same) {

                    if (SelectedContentManager.currentlySelectedContent.length == currentlySelectedContent.length) {

                        for (int i = 0; i < currentlySelectedContent.length && same; i++) {

                            same = currentlySelectedContent[i].sameAs(SelectedContentManager.currentlySelectedContent[i]);
                        }

                        if (same) {

                            return;
                        }
                    }
                }
            }

            SelectedContentManager.tv = tv;
            SelectedContentManager.currentlySelectedContent = currentlySelectedContent;
            SelectedContentManager.viewID = viewID;
        }
    }

    public static void triggerSelectedContentListeners() {
        for (SelectedContentListener l : listeners) {

            try {
                l.currentlySelectedContentChanged(currentlySelectedContent, viewID);

            } catch (Throwable e) {

                Debug.out(e);
            }
        }
    }

    public static ISelectedContent[] getCurrentlySelectedContent() {
        return currentlySelectedContent;
    }

    public static DownloadManager[] getDMSFromSelectedContent() {
        ISelectedContent[] sc = SelectedContentManager.getCurrentlySelectedContent();
        if (sc.length > 0) {
            int x = 0;
            DownloadManager[] dms = new DownloadManager[sc.length];
            for (int i = 0; i < sc.length; i++) {
                ISelectedContent selectedContent = sc[i];
                if (selectedContent == null) {
                    continue;
                }
                dms[x] = selectedContent.getDownloadManager();
                if (dms[x] != null) {
                    x++;
                }
            }
            if (x > 0) {
                System.arraycopy(dms, 0, dms, 0, x);
                return dms;
            }
        }
        return null;
    }

    public static TableView getCurrentlySelectedTableView() {
        return tv;
    }

    public static Object convertSelectedContentToObject(ISelectedContent[] contents) {
        if (contents == null) {
            contents = getCurrentlySelectedContent();
        }
        if (contents.length == 0) {
            return null;
        }
        if (contents.length == 1) {
            return selectedContentToObject(contents[0]);
        }
        Object[] objects = new Object[contents.length];
        for (int i = 0; i < contents.length; i++) {
            ISelectedContent content = contents[i];
            objects[i] = selectedContentToObject(content);
        }
        return objects;
    }

    private static Object selectedContentToObject(ISelectedContent content) {
        Download dl = PluginCoreUtils.wrap(content.getDownloadManager());
        if (dl == null) {
            return null;
        }
        int i = content.getFileIndex();
        if (i < 0) {
            return dl;
        }
        return dl.getDiskManagerFileInfo(i);
    }

}
